1. Field of the Invention
The present invention relates generally to internal combustion engines and more particularly pertains to an apparatus for selectively delivering a fuel additive to such an internal combustion engine, as well as providing a means whereby fuel may be bypassed around a clogged fuel filter to the engine.
2. Description of the Prior Art
The concept of delivering fuel additives to an internal combustion engine is generally well-known in the prior art. In this respect, reference is made to U.S. Pat. No. 3,148,670, issued Sept. 15, 1964, to Fiedler et al., wherein an additive fuel is contained in a pressurized container and is selectively delivered to an internal combustion engine fuel line by a manually operable valve located in the passenger compartment of a vehicle. In this regard, the Fiedler et al. device does not make use of an additive supply contained in a tank positioned within the vehicle, but rather relies upon disposable pressurized containers which, as can be appreciated, are expensive and difficult to obtain.
Another arrangement for supplying an additive to an existing engine fuel system is to be found in U.S. Pat. No. 3,308,794, issued Mar. 14, 1967, to Bailey, wherein there is disclosed an engine fuel system which includes a secondary fuel supply contained in a separate tank and deliverable to the combustion chambers of the engine by means of a pump. In this respect, the pump is automatically operated in response to a depression of an accelerator positioned within the passenger compartment of the vehicle. Specifically, if the accelerator is depressed substantially far so as to require additional fuel to be delivered to the engine, the pump cuts in to provide the additional fuel directly to fuel injectors in communication with the combustion chambers. Of course, the Bailey system does not really envision the use of a fuel additive, but rather only increases the supply of fuel delivered to the combustion chambers during times of need. Additionally, the system is not selectively operable since the pump will always cut in if the accelerator is depressed sufficiently far, and no means are provided for continuing deliverance of fuel to the engine in the event of a fuel filter failure.
Similarly, in U.S. Pat. No. 3,783,849, issued Jan. 8, 1974, to Bramfitt, there is illustrated another duel fuel system wherein a separate tank of volatile fuel is provided for selective delivery to the carburetor of an engine when required. In this connection, an appropriate valve switching system has been designed to allow operation of the engine on the volatile fuel during start and warm-up, and then to switch to normal fuel during warmed-up operation. The self-generation system utilizes engine vacuum as an aid in vaporizing a portion of the normal gasoline, and as can be appreciated, no means for manual operation are provided nor are any means provided for continuing engine operation in the event of a fuel filter failure.
Lastly, U.S. Pat. No. 4,096,839, issued June 27, 1978, to Niertit, discloses an internal combustion engine air-fuel ratio control system which utilizes an oxygen sensor to maintain a desired air-fuel ratio at a first location in an intake manifold to an engine combustion chamber. In this connection, a method and apparatus is disclosed for adding fuel or air to the air-fuel mixture at a second location between the first location and the engine combustion chamber, so that the engine operates at a higher efficiency. However, this system also makes no use of a selective manual injection of a fuel additive nor is there any provision for bypassing clogged fuel filters associated therewith.
As such, it can be recognized that there still exists a need for a system which permits selective admission of a fuel additive for cleaning, lubricating or other purposes into an existing fuel line in combination with a means for bypassing fuel filters should they become clogged. The present invention substantially fulfills this need.